A M&P 45c is next up on my list of future purchases.
I'm one of those folks who have found that I can sometimes really notice a difference of half an inch when it comes to slide/barrel length, as well as even a slight reduction in grip height. Getting in & out of a car seat, and sitting in it, over the course of 8-18 hours a day, as well as desk chairs, can make such things noticeable compared to just standing in front of a mirror.
That being the case, the M&P 45c seems as though it might make me more willing to carry it compared to my full-size M&P 45, which is a great range gun, but just a bit tall in the grip height and long in the slide length.
Dunno. I do know that my full-size M&P 45 has been a surprisingly excellent .45 pistol. One which enjoy shooting more than my TDA alloy .45's or even my 1911's. I'd just like to have one a little bit shorter and less tall in the grip frame for those times I might feel like wearing it as a retirement CCW.
I prefer shooting my M&P 45 to the G21/G21SF, and I also agree that the M&P 45c I handled offers a more desirable grip, overall, compared to the G30. The fact that the grip inserts affect the grip's backstrap profile as well as the palm swell are a nicely done feature.
I was somewhat disappointed that the new Glock model only seems as though it will offer a slight modification of the backstrap profile. Reminds me of the early grip inserts offered on the 99 series.
Oh well, that's what's nice about having a number of options when it comes to good quality offerings from the major makers.